Field of the Invention
The present invention relates generally to the construction and configuration of a stator for electrical machines including both motors and generators, and more particularly to a clam shell stator construction utilizing a split stator core in the form of a pair of half-cylinders with the windings of the stator being supported by a support structure made of non-magnetizable material and having pin connections for phase windings which traverse between the two half-cylinders. The present invention provides a suitable stator structure for use with high magnetic energy permanent magnet, shaft mounted rotors.
In the design and construction of permanent magnet machines, there are three considerations which dictate the design of an improved permanent magnet machine having great appeal to potential purchasers. These three factors are, first, the desire to minimize the cost of the machine, or to provide the most machine for the least money, second, to increase machine efficiency while reducing machine size by utilizing the ever increasing energy product permanent magnets, and third, ease of assembly, disassembly of the machine.
A stator construction and method which substantially satisfies the first two of these design characteristics is disclosed in Assignees U.S. patent applications Ser. No. 06/800,184 issued as U.S. Pat. No. 4,709,180 entitled "Toothless stator Construction for Electrical Machines" and corresponding divisional application No. 07/107,150, Oct. 9, 1987, now U.S. Pat. Ser. No. 4,851,295 entitled "Toothless Stator Electrical Machines Construction Method".
In recent years, high energy product permanent magnets representing significant energy increases over previously known permanent magnets have become available. For example, samarium cobalt permanent magnets previously having an energy product of 27 mega-gauss-oersted (MGO) maximum have recently become available which have an energy product of 30 MGO, and it appears that in the near future an energy product of at least 45 MGO will be achievable by advanced permanent magnets.
A rotor making the maximum use of high energy product permanent magnets is disclosed in Assignee's U.S. Pat. No. 4,667,123, entitled "Two Pole Permanent Magnet Rotor Construction for Toothless Stator Electrical Machines".